Letheo – a Cognitive Runtime for agent memory in Rust (forgetting by physics)

- **Letheo** is an open-source Rust project that provides "cognitive runtime" memory for AI agents — but with a twist: memories decay and are forgotten based on simulated physics (like entropy or half-life), rather than being stored forever. - The name references the river Lethe (forgetfulness) from Greek mythology; "forgetting by physics" means the system probabilistically drops old or unused memories, mimicking human memory decay. - This matters because most agent memory systems (e.g., MemGPT, LangChain's memory) retain everything or use simple time-based eviction. Letheo’s physics-based approach could make long-running agents more biologically plausible and memory-efficient. - Key prior context: "cognitive architectures" (e.g., Soar, ACT-R) have long studied forgetting, but modern LLM agents typically lack principled forgetting. Rust is chosen for performance and safety in low-level memory management — fitting for a runtime focused on memory decay.